The speech is over, but the discussion about what he said and what it means for America and ISIS is just getting started. Tune intoCNN TV and come back to CNN.com for continued news, insights and analysis on Obama and the fight against ISIS.

Sen. Mark Udall, a Colorado Democrat now in a touch re-election fight, issued a statement after President Barack Obama's speech saying that "any expanded U.S. military role beyond airstrikes in the fight against (ISIS) must be approved by Congress." Udall added:

The American people must be assured that we are not pursuing another open-ended conflict in the Middle East, and I will not give this president -- or any other president -- a blank check to begin another land war in Iraq.

by Greg.Botelho9/11/2014 2:09:46 AM

GOP Rep.: Obama speech a start, but not complete

Rep. Marsha Blackburn, R-Tennessee, said that President Barack Obama "laid out the beginnings of a plan," but didn't do everything he needed. She said:

He didn't speak to our allies, and he didn't define our coalition.

by Greg.Botelho9/11/2014 2:02:31 AM

With the 475 additional troops being sent there, how many U.S. troops in Iraq? The below is from CNN's Jim Sciutto -- and does not include 100 more at the U.S. Embassy in Baghdad:

The rapid advance of ISIS through Iraq "and the subsequent brutality they demonstrated" spurred President Barack Obama to change his approach to the Islamist extremist group, said former White House spokesman and current CNN political commentator Jay Carney.

"Those facts have forces a reassessment of the kids of the actions that we need to take and the seriousness of the threat," said Carney.

Sen. John McCain, R-Arizon, said the United States is "paying a heavy price" now for pulling its troops out of Iraq. He said that "we need more" troops in Iraq, though not "to do direct combat."

by Greg.Botelho edited by Sarah Aarthun9/11/2014 1:42:51 AM

What the 475 troops in Iraq will do

Pentagon spokesman Rear Adm. John Kirby gave a breakdown of what the 475 additional U.S. troops headed to Iraq will do:--200 will work out of headquarters command--150 will serve in an "advise and assist" capacity--125 will conduct intelligence, surveillance and reconnaissance "aircraft manning"

by Greg.Botelho9/11/2014 1:40:37 AM

Other parts of the U.S. government weighed in on Twitter, vowing they're ready to implement President Barack Obama's strategy to defeat ISIS. This includes this Tweet from the Pentagon spokesman:

Richard Haas, the president of the Council on Foreign Relations, said that "what was clearly missing from the speech was any sort of a ground partner in Syria." Building up the moderate Syrian opposition is a "long, long proposition, and a risky one at that -- it's divided, it's weak." He added:

The real question is what are we going to use to challenge ISIS on the ground. What are we going to use to take and hold territory. U.S. airpower can't do that. And that, to me, is the Achilles heel of the strategy and that was the missing component of the speech.

by Greg.Botelho9/11/2014 1:35:00 AM

House Speaker John Boehner weighed in on ISIS moments after President Obama's speech:

Jay Carney, a CNN political commentator who until recently was the White House press secretary, notes the irony that Obama -- who campaigned, in part, on a platform of removing U.S. troops from Iraq and Afghanistan -- is pushing for military action in Syria as well as Iraq. But he adds:

Any president has to play the hand he's dealt... I think he's made clear that, as president, he's more than willing and able to make the tough calls to go after the most threatening terrorists in the world, wherever they are.

by Greg.Botelho9/11/2014 1:29:06 AM

White House spokesman Josh Earnest stressed -- as administration officials have done repeatedly in recent weeks -- that the Iraqi government will play a big role in fighting ISIS.

As for timing of airstrikes in Syria, senior admin official: "we’re not going to telegraph our punches..."

by Greg.Botelho9/11/2014 1:27:29 AM

Gingrich: Obama faces 'two big challenges'

Former House Speaker Newt Gingrich said that President Obama faces "two big challenges":

1) "Finding a lot better outcome than Yemen or Somalia," two countries where Gingrich said that terrorists remain active2) Getting other nations -- including Russia and China -- to go along with his plan to go after ISIS

by Greg.Botelho9/11/2014 1:25:37 AM

Brazile: Obama 'challenged us'

Donna Brazile, a CNN political commentator and Democratic strategist, said that President Barack Obama "really challenged us" to come together to fight ISIS.

I thought it was a good speech. A good beginning. And hopefully Congress will pick up the phone and say, 'I'm with you. Let's get this ball rolling.'

by Greg.Botelho9/11/2014 1:22:16 AM

by Greg.Botelho edited by Sarah Aarthun9/11/2014 1:21:52 AM

Newt Gingrich praises Obama speech

Former House Speaker Newt Gingrich, a former GOP presidential candidate, said that he thought "it was a very strong speech overall."

by Greg.Botelho edited by Sarah Aarthun9/11/2014 1:18:55 AM

Gergen: First half of speech was strong

David Gergen, a CNN political analyst and former presidential adviser, said that President Barack Obama did well in the first part of his speech, detailing the country's plans to go after ISIS. But he gave lower marks to Obama "when he shifted ground" and talked about other matters.

The President highlighted what he described as evidence of America's leadership in the world -- pointing to efforts to curb Russia's actions in Ukraine, to contain the Ebola outbreak in West Africa, and to take action in the Middle East. Obama added: "As Americans, we welcome our responsibility to lead ... Tonight, I ask for your support in carrying that leadership forward."

by Greg.Botelho9/11/2014 1:12:48 AM

President Barack Obama stressed that the United States would not go it alone in going after ISIS. He said it will solicit help from other countries, especially Arab nations.

This is American leadership at its best. We stand with people who fight for their own freedom, and we rally other nations on behalf of our common security and common humanity.

by Greg.Botelho9/11/2014 1:09:35 AM

As to Syria, President Obama said that "we must strengthen the (moderate) opposition" fighting -- like ISIS -- to unseat Syrian President Bashar al-Assad.

by Greg.Botelho edited by Sarah Aarthun9/11/2014 1:08:32 AM

President Obama announced that he'll send 475 more U.S. troops to Iraq to help with the fight against ISIS there -- though not to participate in the ground war.

by Greg.Botelho9/11/2014 1:07:32 AM

President Obama vowed that the U.S.-led coalition "will conduct a systematic campaign of airstrikes against these terrorists." He added that "he will not hesitate to take action against (ISIS) in Syria as well as Iraq.

by Greg.Botelho9/11/2014 1:06:18 AM

Obama said that U.S. airstrikes targeting ISIS in Iraq have helped Iraqi and Kurdish fighters, as well as "helped save the lives" of thousands of innocent civilians.

by Greg.Botelho9/11/2014 1:05:20 AM

President Barack Obama that, "if left unchecked," ISIS could pose a threat beyond the Middle East. He said that intelligence indicates "thousands of foreigners" have joined the group in its fight in Iraq and Syria.

by Greg.Botelho9/11/2014 1:04:37 AM

President Barack Obama said "ISIL is not Islamic," saying most of the group's victims were Muslim. He added:

ISIL is a terrorist organization, pure and simple. And it has no vision other than the slaughter of all who stand in its way.

by Greg.Botelho9/11/2014 1:02:56 AM

President Barack Obama began his speech Wednesday by highlighting his administration's counterterrorism efforts:

As commander-in-chief, my highest priority is the security of the American people.

by Greg.Botelho9/11/2014 12:59:24 AM

Gergen outlines 3 priorities for Obama

David Gergen, a former president adviser and senior political analyst for CNN, says that President Barack Obama needs to do three things in his speech tonight:

1) "He needs to be very clear that his mission is to destroy ISIS"2) "We need to understand how he's going to use airpower"3) "We need to know about American troops"

by Greg.Botelho9/11/2014 12:53:55 AM

Rep. King: Obama should act now, get Congress' OK later

President Barack Obama shouldn't wait on Congress to act against ISIS in Syria, Rep. Peter King told CNN.

Obama should "start doing whatever he has to do now," and then Congress should "come back and adopt a resolution ratifying what the President is doing," the New York Republican said.

"We should go on record supporting what the President is doing, because this is going to go on ... for at least several years," King said.

by Greg.Botelho9/11/2014 12:50:52 AM

GOP Rep.: Obama should vow we'll do 'whatever is necessary'

Rep. Peter King, R-New York, said that he hopes President Obama on Wednesday night says "he will do whatever is necessary to ultimately destroy ISIS and beginning as quickly as possible."

"We have to accept the fact that this is going to be long and protracted," said King, the chairman of the House's subcommittee on counterterrorism and intelligence.

by Greg.Botelho9/11/2014 12:43:42 AM

Ex-general: A very complex mission

Retired U.S. Army Lt. Gen. Mark Hertling said that U.S.-led efforts to defeat ISIS in Syria, as well as Iraq, will be a daunting challenge.

"There are borders that we didn't have to consider within Iraq," Hertling told CNN. "This takes what we did in Iraq -- which ... was extremely complex, the most complex counterinsurgency that you'll ever find -- and multiplies it by a form of about 100. This is very tough."

by Greg.Botelho9/11/2014 12:36:49 AM

Obama has talked Syria before

President Barack Obama has talked to the American public before about what to do inSyria. At that time, in 2012, he was addressing the use of chemical weapons by forces loyal to Syrian President Bashar al-Assad.

A Syrian opposition official tells CNN's Jim Sciutto that rebel leaders are "very pleased" with the steps they expect President Barack Obama will outline tonight as part of the U.S. strategy to go after ISIS.

In particular, the official believes that having the United States overtly train and equip moderate rebels trying to unseat Syrian President Bashar al-Assad is a "game-changer" that will allow the mission to expand significantly.

by Greg.Botelho9/10/2014 10:36:55 PM

More like Somalia than AfghanistanWhat is that strategy? President Barack Obama suggested that people look at what the United States has done in Yemen and Somalia to go after terrorists. In both cases, U.S. airpower has been deployed in conjunction with allied ground troops.

According to the excerpts, the President will say:

I want the American people to understand how this effort will be different from the wars in Iraq and Afghanistan. It will not involve American combat troops fighting on foreign soil. This counterterrorism campaign will be waged through a steady, relentless effort to take out ISIL wherever they exist using our air power and our partner forces on the ground.

by Greg.Botelho9/10/2014 10:33:46 PM

'Our objective is clear'The excerpts restate what Obama has said in recent days about goals for any action: to "degrade, and ultimately destroy" ISIS as part of what he called "a comprehensive and sustained counterterrorism strategy."

by Greg.Botelho9/10/2014 10:30:15 PM

'A broad coalition'

The White House has offered a glimpse of President Barack Obama's comments tonight, including what his administration plans to do about ISIS in the big-picture:

I can announce thatAmerica will lead a broad coalition to roll back the terrorist threat.

by Rachel Clarke9/10/2014 7:43:51 PM

Good afternoon

Thanks for joining us as we gear up to hear what President Obama will say tonight in his national address on the threat from the ISIS terror group.

We'll be live blogging from about 8 p.m. ET, giving you the latest news and analysis as we await the speech that's set to begin a little after 9. Stay with us for the speech and the early reaction.

Looks like the President might be getting some last-minute input. White House photographer Pete Souza just posted this photo, showing Obama in the Situation Room with his national security team.